15f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)// Copyright 2014 The Chromium Authors. All rights reserved. 25f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)// Use of this source code is governed by a BSD-style license that can be 35f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)// found in the LICENSE file. 45f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 55f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#ifndef CHROME_BROWSER_FONT_FAMILY_CACHE_H_ 65f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#define CHROME_BROWSER_FONT_FAMILY_CACHE_H_ 75f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 85f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include "base/containers/hash_tables.h" 95f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include "base/gtest_prod_util.h" 105f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include "base/prefs/pref_change_registrar.h" 115f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include "base/strings/string16.h" 125f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include "base/supports_user_data.h" 135f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include "content/public/browser/notification_observer.h" 145f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include "content/public/browser/notification_registrar.h" 155f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#include "content/public/common/web_preferences.h" 165f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 175f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)class PrefService; 185f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)class Profile; 195f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 205f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)FORWARD_DECLARE_TEST(FontFamilyCacheTest, Caching); 215f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 225f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)// Caches font family preferences associated with a PrefService. This class 235f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)// relies on the assumption that each concatenation of map_name + '.' + script 245f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)// is a unique string. It also relies on the assumption that the (const char*) 255f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)// keys used in both inner and outer hash_maps are compile time constants. 265f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)class FontFamilyCache : public base::SupportsUserData::Data, 275f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) public content::NotificationObserver { 285f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) public: 295f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) explicit FontFamilyCache(Profile* profile); 305f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) virtual ~FontFamilyCache(); 315f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 325f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Gets or creates the relevant FontFamilyCache, and then fills |map|. 335f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) static void FillFontFamilyMap(Profile* profile, 345f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) const char* map_name, 355f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) content::ScriptFontFamilyMap* map); 365f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 375f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Fills |map| with font family preferences. 385f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) void FillFontFamilyMap(const char* map_name, 395f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) content::ScriptFontFamilyMap* map); 405f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 415f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) protected: 425f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Exposed and virtual for testing. 435f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Fetches the font without checking the cache. 445f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) virtual base::string16 FetchFont(const char* script, const char* map_name); 455f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 465f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) private: 475f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) FRIEND_TEST_ALL_PREFIXES(::FontFamilyCacheTest, Caching); 485f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 495f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Map from script to font. 505f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Key comparison uses pointer equality. 515f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) typedef base::hash_map<const char*, base::string16> ScriptFontMap; 525f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 535f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Map from font family to ScriptFontMap. 545f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Key comparison uses pointer equality. 555f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) typedef base::hash_map<const char*, ScriptFontMap> FontFamilyMap; 565f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 575f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Checks the cache for the font. If not present, fetches the font and stores 585f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // the result in the cache. 595f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // This method needs to be very fast, because it's called ~20,000 times on a 605f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // fresh launch with an empty profile. It's important to avoid unnecessary 615f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // object construction, hence the heavy use of const char* and the minimal use 625f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // of std::string. 635f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // |script| and |map_name| must be compile time constants. Two behaviors rely 645f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // on this: key comparison uses pointer equality, and keys must outlive the 655f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // hash_maps. 665f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) base::string16 FetchAndCacheFont(const char* script, const char* map_name); 675f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 685f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Called when font family preferences changed. 695f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Invalidates the cached entry, and removes the relevant observer. 705f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Note: It is safe to remove the observer from the pref change callback. 715f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) void OnPrefsChanged(const std::string& pref_name); 725f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 735f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // content::NotificationObserver override. 745f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Called when the profile is being destructed. 755f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) virtual void Observe(int type, 765f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) const content::NotificationSource& source, 775f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) const content::NotificationDetails& details) OVERRIDE; 785f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 795f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Cache of font family preferences. 805f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) FontFamilyMap font_family_map_; 815f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 825f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Weak reference. 835f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Note: The lifetime of this object is tied to the lifetime of the 845f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // PrefService, so there is no worry about an invalid pointer. 855f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) const PrefService* prefs_; 865f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 875f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Reacts to profile changes. 885f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) PrefChangeRegistrar profile_pref_registrar_; 895f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 905f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) // Listens for profile destruction. 915f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) content::NotificationRegistrar notification_registrar_; 925f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 935f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) DISALLOW_COPY_AND_ASSIGN(FontFamilyCache); 945f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)}; 955f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles) 965f1c94371a64b3196d4be9466099bb892df9b88eTorne (Richard Coles)#endif // CHROME_BROWSER_FONT_FAMILY_CACHE_H_ 97